Fluorocarbon based fluids have found widespread use in industry in a number of applications, including as refrigerants, aerosol propellants, blowing agents, heat transfer media, and gaseous dielectrics. Because of the suspected environmental problems associated with the use of some of these fluids, including the relatively high global warming potentials associated therewith, it is desirable to use fluids having low or even zero ozone depletion potential. Additionally, the use of single component fluids or azeotropic mixtures, which do not fractionate on boiling and evaporation, is desirable. However, the identification of new, environmentally safe, non-fractionating mixtures is complicated due to the fact that azeotrope formation is not readily predictable.
The industry is continually seeking new fluorocarbon based mixtures that offer alternatives, and are considered environmentally safer substitutes for CFCs and HCFCs.
The Montreal Protocol for the protection of the ozone layer, signed in October 1987, mandates the phase out of the use of chlorofluorocarbons (CFCs). Materials more “friendly” to the ozone layer, such as hydrofluorocarbons (HFCs) eg HFC-134a replaced chlorofluorocarbons. The latter compounds have proven to be green house gases, causing global warming and were regulated by the Kyoto Protocol on Climate Change, signed in 1998. The emerging replacement materials, hydrofluoropropenes, were shown to be environmentally acceptable ie have zero ozone depletion potential (ODP) and acceptable low GWP.
Currently proposed replacement refrigerants for hydrofluorocarbons such as HFC-134a include HFC-152a, pure hydrocarbons such as butane or propane, or “natural” refrigerants such as CO2. Many of these suggested replacements are, flammable, and/or have low energy efficiency. Therefore, new alternative refrigerants are being sought. Fluoroolefin materials such as hydrofluoropropenes and/or hydrochlorofluoropropenes have generated interest as replacements for HFCs.
The object of the present invention is to provide novel compositions that can serve as refrigerant and heat transfer fluids as well as blowing agents, solvent cleaners etc. that provide unique characteristics to meet the demands of low or zero ozone depletion potential and lower global warming potential as compared to the current HFCs.